CA1238880A - Articulation for tower crane boom that has a parking position - Google Patents
Articulation for tower crane boom that has a parking positionInfo
- Publication number
- CA1238880A CA1238880A CA000461335A CA461335A CA1238880A CA 1238880 A CA1238880 A CA 1238880A CA 000461335 A CA000461335 A CA 000461335A CA 461335 A CA461335 A CA 461335A CA 1238880 A CA1238880 A CA 1238880A
- Authority
- CA
- Canada
- Prior art keywords
- boom
- tower
- joint
- fixed axis
- pair
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B66—HOISTING; LIFTING; HAULING
- B66C—CRANES; LOAD-ENGAGING ELEMENTS OR DEVICES FOR CRANES, CAPSTANS, WINCHES, OR TACKLES
- B66C23/00—Cranes comprising essentially a beam, boom, or triangular structure acting as a cantilever and mounted for translatory of swinging movements in vertical or horizontal planes or a combination of such movements, e.g. jib-cranes, derricks, tower cranes
- B66C23/18—Cranes comprising essentially a beam, boom, or triangular structure acting as a cantilever and mounted for translatory of swinging movements in vertical or horizontal planes or a combination of such movements, e.g. jib-cranes, derricks, tower cranes specially adapted for use in particular purposes
- B66C23/26—Cranes comprising essentially a beam, boom, or triangular structure acting as a cantilever and mounted for translatory of swinging movements in vertical or horizontal planes or a combination of such movements, e.g. jib-cranes, derricks, tower cranes specially adapted for use in particular purposes for use on building sites; constructed, e.g. with separable parts, to facilitate rapid assembly or dismantling, for operation at successively higher levels, for transport by road or rail
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- Engineering & Computer Science (AREA)
- Structural Engineering (AREA)
- Transportation (AREA)
- Mechanical Engineering (AREA)
- Jib Cranes (AREA)
Abstract
ARTICULATION FOR TOWER CRANE BOOM
THAT HAS A PARKING POSITION
Abstract of the Disclosure The inner end of a tower crane boom is connected to the top of its tower by two lugs fixed on the tower, each having an upwardly opening slot, and two trunnions fixed on the inner end portion of the boom, one for each lug, each rotatably seatable in the rounded bottom of the slot in its lug. The slot bottom in one lug defines a first fixed axis, midway between the front and rear sides of the tower, about which the boom swings in its range of working positions; that in the other lug defines a second fixed axis, near the front side of the tower, about which the boom swings to and from an inopera-tive position wherein it extends along the front side of the tower. The distance between the trunnion axes equals the distance between the fixed axes. Links confine the boom against moving to a position in which neither trunnion is seated in the slot in its lug. Each link has a pivot connection with the tower at a fixed axis defined by one lug and a pivot connection with the boom at the axis defined by the trunnion for the other lug. Preferably, lugs, trunnions and links are duplicated at opposite sides of a vertical plane of symmetry.
THAT HAS A PARKING POSITION
Abstract of the Disclosure The inner end of a tower crane boom is connected to the top of its tower by two lugs fixed on the tower, each having an upwardly opening slot, and two trunnions fixed on the inner end portion of the boom, one for each lug, each rotatably seatable in the rounded bottom of the slot in its lug. The slot bottom in one lug defines a first fixed axis, midway between the front and rear sides of the tower, about which the boom swings in its range of working positions; that in the other lug defines a second fixed axis, near the front side of the tower, about which the boom swings to and from an inopera-tive position wherein it extends along the front side of the tower. The distance between the trunnion axes equals the distance between the fixed axes. Links confine the boom against moving to a position in which neither trunnion is seated in the slot in its lug. Each link has a pivot connection with the tower at a fixed axis defined by one lug and a pivot connection with the boom at the axis defined by the trunnion for the other lug. Preferably, lugs, trunnions and links are duplicated at opposite sides of a vertical plane of symmetry.
Description
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ARTICUI,ATION FOR TOWER CRANE BOOM
THAT HAS A PARKING POSITION
Field of the Invention This invention relates to tower cranes having a sub-stantially upright tower and having a boom connected with the top of the tower to swing up and down through a range of for-wardly projecting working positions; and the invention is moreparticularly concerned with articulat~ion means for a tower crane whereby the boom is so connected with the tower as to provide two horizontally spaced apart axes about which the boom can swing, one of those axes being midway between the front and back sides of the tower and being the axis about which the boom swings through its range of working positions, and the other being near the front side of the tower and being an axis about which the boom swings to and from an inoperative parking position in which it extends down along the front side of the tower.
Background of the Prior Art The upright boom of a large tower crane can extend to a height of well over 150 ft. (45 m.), and the boom that pro-jects forward from the tower may have a length which is only slightly less than the height of the tower. When the crane is working, the boom is swung up and down through an operating range that can carry it from about 15 to about 75 above the horizontal, for moving a hoisted load toward and from the base of the crane. Because of the height of the tower and the length of the boom, it is desirable to enable the boom to be swung to an inoperative parking position in which the boom ;
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extends dGwn alongside the tower. In that position ~f the boom, high winds exert less force and leverage against it, so that the crane is less likely to be tipped over by a high wind. The boom is also brought to this inoperative position when the tower is to be lowered, the tower then being swung forwardly down to a horizontal position in which the b`oom underlies it.
For the bo~m to be brought to its inoperative position, it must swing down from its lowermost working position about an axis that is at least a short distance in front of the front side of the tower. In its range of working positions, however, the boom should preferably swing about an axis that is centered on the top of the tower -- that is, midway between the front and rear sides of the tower -- so that the forces that the boom exerts upon its pivot axis do not impose bending moments upon the tower.
In most prior tower cranes, the axis about which the boom swung through its range of working positions was also the axis about which it swung to and from its inoperative position, and that axis was located at or slightly in front of the front side of the tower. To support the bending loads that are imposed upon the tower with the boom axis in this off-center location, the tower must be built with substantially greater strength than would be needed if the boom pivot axis were centered over the tower in the working range of the boom, thus increasing the cost o~ the tower and raising the center of graVity of the crane as a whole.
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Some difficult problems are involved in shifting the axis about which the boom swings, because all control of the boom must be exerted from near the bottom of the tower. For sa~ety, it should not be possible to lower the boom below the lower part of its working range unless its swinging axis has been shifted to the forward position, and the boom should not be allowed to swing in its working range until its swinging axis has been shifted back to where it is centered over the tower.
Obviously, any expedient for shifting the boom axis must be so sturdy and simple as to be extremely reliable, but should never-theless be inexpensive and relati~el~ light in weight.
Summary of the Invention The general object of the present invention is to provide an articulation between the top of the tower of a tower crane and a boom which projects forwardly from the tower when in a range of working positions, said artlculation defining two axes about which the boom can swing, one of them being cen-tered o~er the tower, midway between its front and rear sides and being the axis about which the boom swings in its range of working positions, the other being adjacent to the front side of the tower and being an axis about which the boom swings to and from an inoperative position in which it extends down along the front side of the tower, said articulation being so arranged that there is an automatic transfer from one to the other of these axes as the boom swings through a transitional position that is between the range of its working positions and a lower range of nonoperating positions in which it swings to and from its inoperative position.
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It is also a general object of this invention to provide an articulation of the character just described that is extremely sturdy and reliable but nevertheless light in weight, low in cost, automatic in performing its function of shifting the axis about which the boom swings, and compatible with latching means whereby the boom is releasably confined in its inoperative position.
According to the invention there is provided a crane comprising an upright tower that has a top and front and rear sides, a boom that has an outer end from which a load hoisting cable can depend and an inner end, and articulation means providing a connection be-tween said top of said tower and said inner end of said boom where-by said boom can swing through a range of upwardly projecting pos-itions above horizontal about a horizontal rear fixed axis that is located at said top of said tower between said front and rear sides of said tower and whereby said boom can swing through a range of downwardly projecting positions below horizontal about a horizontal forward fixed axis that is located at said top of said tower and spaced forwardly from and parallel to said rear fixed axis said downwardly projecting positions including an inoperative position wherein said boom extends substantially vertically downward along said front side of said tower said articulation means comprising:
A. at least one rear pair of engageable and disengageable joint elements (1) said rear pair comprising (a) a rear tower joint element fixed on the top of said tower on said rear fixed axis and (b) an associated rear boom joint element fixed on said inner end of said boom ~L~3~
B. at least one forward pair of engageable and disengageable joint elements (1) said forward pair comprising ~a) a forward tower joint element fixed on the top of said tower on said forward fixed axis and (b) an associated forward boom joint element fixed on said boom at a location outwardly of said rear boom joint element at a dis-tance equal to that between said rear and forward axes, (2I) one joint element of said pair comprising a trunnion and (3) the other joint element of each forward pair comprising a slot (a) with a closed end that defines a seat on which the trunnion of an associated element can rotate when engaged therewith and (b) with an opposite open end to enable engagement and disen-gagement of the trunnion of an associated element in the course of substantially vertical relative motion of the boom joint ele-ments;
(4) said boom being swingable through said downwardly projecting positions about said forward fixed axis when said forward pair of joint elements are engaged and said rear pair of joint ele~
ments are disengaged;
(5) said boom being swingable through said upwardly projecting positions about said rear fixed axis when said rear pair of joint elements are engaged and said forward pair of joint elements are disengaged.
C. at least one elongated first link having (1) one end pi~otally connected to the top of $aid tower on said rear fixed axis and ~3~8~
ARTICUI,ATION FOR TOWER CRANE BOOM
THAT HAS A PARKING POSITION
Field of the Invention This invention relates to tower cranes having a sub-stantially upright tower and having a boom connected with the top of the tower to swing up and down through a range of for-wardly projecting working positions; and the invention is moreparticularly concerned with articulat~ion means for a tower crane whereby the boom is so connected with the tower as to provide two horizontally spaced apart axes about which the boom can swing, one of those axes being midway between the front and back sides of the tower and being the axis about which the boom swings through its range of working positions, and the other being near the front side of the tower and being an axis about which the boom swings to and from an inoperative parking position in which it extends down along the front side of the tower.
Background of the Prior Art The upright boom of a large tower crane can extend to a height of well over 150 ft. (45 m.), and the boom that pro-jects forward from the tower may have a length which is only slightly less than the height of the tower. When the crane is working, the boom is swung up and down through an operating range that can carry it from about 15 to about 75 above the horizontal, for moving a hoisted load toward and from the base of the crane. Because of the height of the tower and the length of the boom, it is desirable to enable the boom to be swung to an inoperative parking position in which the boom ;
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extends dGwn alongside the tower. In that position ~f the boom, high winds exert less force and leverage against it, so that the crane is less likely to be tipped over by a high wind. The boom is also brought to this inoperative position when the tower is to be lowered, the tower then being swung forwardly down to a horizontal position in which the b`oom underlies it.
For the bo~m to be brought to its inoperative position, it must swing down from its lowermost working position about an axis that is at least a short distance in front of the front side of the tower. In its range of working positions, however, the boom should preferably swing about an axis that is centered on the top of the tower -- that is, midway between the front and rear sides of the tower -- so that the forces that the boom exerts upon its pivot axis do not impose bending moments upon the tower.
In most prior tower cranes, the axis about which the boom swung through its range of working positions was also the axis about which it swung to and from its inoperative position, and that axis was located at or slightly in front of the front side of the tower. To support the bending loads that are imposed upon the tower with the boom axis in this off-center location, the tower must be built with substantially greater strength than would be needed if the boom pivot axis were centered over the tower in the working range of the boom, thus increasing the cost o~ the tower and raising the center of graVity of the crane as a whole.
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Some difficult problems are involved in shifting the axis about which the boom swings, because all control of the boom must be exerted from near the bottom of the tower. For sa~ety, it should not be possible to lower the boom below the lower part of its working range unless its swinging axis has been shifted to the forward position, and the boom should not be allowed to swing in its working range until its swinging axis has been shifted back to where it is centered over the tower.
Obviously, any expedient for shifting the boom axis must be so sturdy and simple as to be extremely reliable, but should never-theless be inexpensive and relati~el~ light in weight.
Summary of the Invention The general object of the present invention is to provide an articulation between the top of the tower of a tower crane and a boom which projects forwardly from the tower when in a range of working positions, said artlculation defining two axes about which the boom can swing, one of them being cen-tered o~er the tower, midway between its front and rear sides and being the axis about which the boom swings in its range of working positions, the other being adjacent to the front side of the tower and being an axis about which the boom swings to and from an inoperative position in which it extends down along the front side of the tower, said articulation being so arranged that there is an automatic transfer from one to the other of these axes as the boom swings through a transitional position that is between the range of its working positions and a lower range of nonoperating positions in which it swings to and from its inoperative position.
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It is also a general object of this invention to provide an articulation of the character just described that is extremely sturdy and reliable but nevertheless light in weight, low in cost, automatic in performing its function of shifting the axis about which the boom swings, and compatible with latching means whereby the boom is releasably confined in its inoperative position.
According to the invention there is provided a crane comprising an upright tower that has a top and front and rear sides, a boom that has an outer end from which a load hoisting cable can depend and an inner end, and articulation means providing a connection be-tween said top of said tower and said inner end of said boom where-by said boom can swing through a range of upwardly projecting pos-itions above horizontal about a horizontal rear fixed axis that is located at said top of said tower between said front and rear sides of said tower and whereby said boom can swing through a range of downwardly projecting positions below horizontal about a horizontal forward fixed axis that is located at said top of said tower and spaced forwardly from and parallel to said rear fixed axis said downwardly projecting positions including an inoperative position wherein said boom extends substantially vertically downward along said front side of said tower said articulation means comprising:
A. at least one rear pair of engageable and disengageable joint elements (1) said rear pair comprising (a) a rear tower joint element fixed on the top of said tower on said rear fixed axis and (b) an associated rear boom joint element fixed on said inner end of said boom ~L~3~
B. at least one forward pair of engageable and disengageable joint elements (1) said forward pair comprising ~a) a forward tower joint element fixed on the top of said tower on said forward fixed axis and (b) an associated forward boom joint element fixed on said boom at a location outwardly of said rear boom joint element at a dis-tance equal to that between said rear and forward axes, (2I) one joint element of said pair comprising a trunnion and (3) the other joint element of each forward pair comprising a slot (a) with a closed end that defines a seat on which the trunnion of an associated element can rotate when engaged therewith and (b) with an opposite open end to enable engagement and disen-gagement of the trunnion of an associated element in the course of substantially vertical relative motion of the boom joint ele-ments;
(4) said boom being swingable through said downwardly projecting positions about said forward fixed axis when said forward pair of joint elements are engaged and said rear pair of joint ele~
ments are disengaged;
(5) said boom being swingable through said upwardly projecting positions about said rear fixed axis when said rear pair of joint elements are engaged and said forward pair of joint elements are disengaged.
C. at least one elongated first link having (1) one end pi~otally connected to the top of $aid tower on said rear fixed axis and ~3~8~
(2) an opposite end pivotally connected to said boom on the same axis as said forward boom joint element;
D. at least one elongated second link having (l) one end fixedly connected to said boom on the same axis as said rear boom joint element and (2) an opposite end pivotally connected to the top of said tow-er on said forward fixed axis;
D. at least one elongated second link having (l) one end fixedly connected to said boom on the same axis as said rear boom joint element and (2) an opposite end pivotally connected to the top of said tow-er on said forward fixed axis;
(3) said first and second links being operable to prevent said boom from moving relative to said tower to a position in which neither of said rear or forward pairs of joint elements is en-gaged; and E. means connected to said boom to effect swinging movement of said boom about either one of said rear fixed axis or said forward fixed axis.
Brief Description of the Drawings In the accompanying drawings, which illustrate what is now regarded as a preferred embodiment of the invention:
Figure l is a view in side elevation of a tower crane em-bodying the principles of this invention with the boom in working position;
Figure 2 is a view similar to Figure l but showing the boom in its inoperative position;
Figure 3 is a top plan view of the articulation means of this invention;
~23~388~) Fig. 4 is a perspective viPw of the articulation means as seen from above and to the rear of the top of the tower;
Figs. 5, 6 and 7 are fragmentary views in side elevation showing successiye conditions of the articulation means as the boom swings down from the lower part of its range of working positions to its inoperative position.
Detailed Description of Preferred Embodiment of the In~ention A tower crane that embodies the principles of this in-Yention comprises a high upright tower 5 and a boom 6 that hasan outer end from which a load hoisting cable 7 depends and an inner end portion that is connected to the top of the tower 5 by means of articulation means 8 of this invention. The crane in this case has a base 10 equipped with crawler treads and comprises the usual platform 11 ~hich is mounted on the base for rotation relatiye to it about a vertical sluing axis.
The platform 11 in turn supports the tower 5 as well as such conyentional elements as an operator's cab, engine and winches.
When the crane is in operation, the boom 6 projects for-ward from the top of the tower 5, as shown in Fig. 1, and isswingable relati~e to the tower in a vertical plane, through a range of working positions in which the longitudinal center-line of the boom makes upward angles to the horizontal of between about 15 and 75. Such yertical swinging of the boom 6 enables a hoisted load to be moved towards and from the base 10 of the machine, while sluing motion provides for moving the hoisted load to the left and right. Vertical swinging of .
~238~380 the boom 6 in its range of working positions takes place about a first fixed axis F-l, which is defined by a first pair of engageable and disengageable joint elements as ex-plained hereinafter. That first fixed axis F-l is located midway between the front side 13 and the rear side 14 of the tower, so that the load forces imposed upon the top of the tower through that axis are centered relative to the tower and therefore impose no bending moments upon it.
As the boom is allowed to swing below its range of working positions, it passes through a transition position in which it extends substantially horizontally and in which a second pair of cooperating joint elements tdescribed herein-after) are automatically engaged to define a second fixed axis F-2, which is spaced a small distance forward of the front side 13 of the tower and ~hich is parallel to the first axis F-l. With continued downward swinging of the boom, the cooperating joint elements of the first pair are disengaged and the boom swings about the second axis F-2 until it reaches the inoperative or parking position shown in Fig. 2, wherein it extends downward along the front side of the boom. In swinging upward from the inoperative position, the boom first swings about the second or front axis F-2 until it reaches the above mentioned transition position, and then swings about the first axis F-l.
The articulation means 8 of this in~ention, which com-prises the cooperating joint elements that define these alternatively employed axes, is described in detail hereinafter.
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At this point, however, certain other features should be noted in a crane that comprises the articulation means 8 of this invention.
The first axis F-l, which is centered on the tower 5 and about which the boom 6 swings in its range of working positions, extends across the inner end of the boom and is of course horizontal and transverse to the length of the boom.
However, the second or forward axis P-2 is spaced outwardly along the boom from its inner end, and therefore when the boom is in its inoperative position a short inner end portion 15 of it, substantially e~ual in length to the distance be-tween the fixed axes, projects above the top of the tower, as shown in Figs. 2 and 7.
For actuating the boom 6 to swing between its inoperative and its working positions, and through its range of working positions, a strut 17 is fixed on the inner end of the boom, extending substantially at right angles to the boom to project upward when the boom is in its working positions and to pro-ject forward when the boom is in its inoperative position. A
rigid diagonal brace 18 is connected between the strut 17 and the boom ~, and a pendant or tension cable 19 is connected between the tip of the strut 17 and the outer end of the boom. In like manner there is a strut 20 that projects rear-ward from the top of the tower 5, supported by a rigid brace 21 that extends diagonally down to the tower and having a pendant 22 connected between its tip and the bottom portion of the tower. A cable 2~ for actuating the boom 6 in its vertical swinging extends up from one of the winches, around ~238~31(~
an idler sheave 25 that is at the rear side of the tower and a distance below its top, thence around shea~es 26 at the tip of the horizontal strut 20, through sheaves 27 on the tip of the boom-carried strut 17, and back to a fixed connection 28 at the tip of the horizontal strut 20. It will be apparent that when this cable 24 is wound in, the tip of the strut 17 i5 drawn towards the tip of the horizontal strut 20, raising the outer end of the boom; whereas unwinding the cable 24 allows the outer end of the boom to descend. secause the strut 17 is mounted on the very inner end of the boom, which is above the leYel of the horizontal strut 20 when the boom is in its inoperative position (see Fig. 2) the two struts 17 and 20 can cooperate with the cable 24 for raising the boom from its inoperative position. Note that, for simplicity, the strut 17 is not shown in Figs. 3-7.
The base portion of the tower 5 is pivoted to the platform 11 so that the tower can be swung down forwardly from its erected position shown in the drawings to a horizontal position in which the boom 6 underlies it. Before the tower is swung down, the boom, in its inoperative position, is releasably latched to the tower, known latching means (not shown) being arranged to effect such latching automatically when the tower reaches its inoperative position. The latching means is of course manually released after the tower is erected and when the boom is to be swung up to its range of working positions.
The ~eans for swinging the tower between its erected and its horizontal positions is also known, comprising a gantry 30.
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The articulation means 8 of this invention comprises a tower cap 32 that is fixed to the top o~ the tower and has a pair of legs 33 that project forward beyond the front side 13 of the tower. Fixed to the top of the tower cap are rear and front tower joint elements 35, 36 which respectively define the two fixed axes F-l and F-2 about which the boom swings and which cooperate with respective boom joint elements 37 and 38 that are fixed on the inner end portion of the boom. In this case the boom joint elements 37, 38 comprise trunnions and the tower joint elements 35, 36 comprise upwardly projecting lugs in which there are upwardly opening slots 41, 42 wherein the trunnions 37, 38 are respectively receivable; but it will be obvious that this relationship could be reversed in that the tower joint elements could comprise fixed trunnions and the boom joint elements could comprise lugs with downwardly opening slots.
As shown and preferred, each of the joint elements com-prises duplicate members spaced equal distances to opposite sides of a vertical plane of symmetry that contains the longitudinal centerlines of the tower and the boom. Thus the rear tower joint element 35 comprises a pair of upwardly projecting lugs on the tower cap 32, one near each lateral side of the tower, and the front tower joint element 36 like-wise comprises a pair of upwardly projecting lugs, one fixed on the front end of each of the leg portions 33 of the tower cap. The upwardly opening slot 41, 42 in every lug 35, 36 has a semicircular bottom end in which a trunnion is closely 1;~3~88~
rotatably receivable, the arcs of the bottom ends of these slots having their centers on the respective fixed axes F-l, F-2.
Each boom joint element 37, 38 comprises two coaxial trunnions that are spaced to opposite sides of the vertical plane of symmetry by a distance such as to be receivable in the slots of the lugs 35, 36 that comprise the cooperating tower joint element. Specifically, as best seen in Fig. 4, the inner end portion of the boom is U-shaped to have a pair of legs 44, and at the extreme inner end of the boom each leg 44 is in turn bifurcated and one of the coaxial trunnions that comprise the rear boom joint element 37 bridges across the bifurcations. As each of these trunnions 37 is recei~ed in a slot 41 of the rear tower joint element 35, the bifurca-tions of the boom leg overlie opposite faces of the lug thatcontains the slot 41, confining the boom against movement in directions along the boom axes. It will be seen that the trunnions that comprise the rear boom joint element 37 define a first boom axis B-l that coincides with the first fixed axis F-l when those trunnions are received in the slots 41, that is, when the boom joint element 37 is engaged with its cooperating tower joint element 35.
The coaxial trunnions that comprise the front boom joint element 38 are anchored in the legs 44 of the U-shaped inner end portion of the boom and project laterally outwardly from those legs. The legs 44 thus have their laterally outer faces close to the inner faces of the lugs that comprise the front tower joint element, 36 when the front joint elements 36, 38 ~23~ 30 are engaged, thereby cGnfining the boom against moYement parallel to the fixed axes F-l, F-2. It will be seen that the coaxial trunnions that comprise the front boom joint ele-ment 38 define a second or front boom axis B-2 that is parallel to the first boom axis B-l and is spaced from it by a distance e~ual to the distance between the fixed axes F-l and F-2, and the front boom axis B-2 coincides with the front fixed axis F-2 when the front joint elements 36, 38 are engaged.
It will be evident that when the boom is in its ranye of working positions the rear joint elements 35, 37 are engaged and the boom swings about the coinciding axes F-l and B-l; and when the boom is swinging to and from its inoperati~e position the front joint elements 36, 38 are engaged and the boom swings about the coinciding front axes F-2 and B-2. Because the boom axes B-l, B-2 are spaced apart by the same distance as the fixed axes F-l, F-2, the boom has a transition position, just below its range of working positions, in which both boom joint elements 37, 38 are fully engaged with their respectively cooperating tower joint elements 35, 36; and the boom passes through that transition position in the course of transferring its swinging motion from one to the other of the fixed axes F-l, F-2.
It will be evident that the boo~ must be constrained against moYement to a position in which neither pair of cooperating joint elements 35, 37 or 36, 38 is engaged. To that end, two link means 47 and 49 are connected between the tower cap and the boom, each link means in this case com-prising a pair of elongated and parallel links that are spaced . I .
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equal distances to opposite sides of the plane of symmetry.
Each of the link means 47, 49 has at one end thereof a pivotal connection to the tower that is rotatable about the fixed axis F-l, F-2 defined by the tower joint element 35, 36 of one of the cooperating pairs of joint elements, and has at its other end a connection to the boom that is rotatable about the boom axis B-2, s-l defined by the boom joint element 38, 37 of the other cooperating pair of joint elements.
As here shown, one link means 47 comprises a pair of individual links that lie inwardly adjacent to the legs 44 of the U-shaped inner end portion of the boom. The rear end of each of those two links pivots about a short trunnion 51 carried by laterally spaced upwardly projecting lugs 52 that are fixed on the tower cap, the axes of said trunnions 51 coinciding with the rear fixed axis F-l defined by the rear tower joint element 37. The front end of each of those individual links pivots about a trunnion 53 that projects inwardly from a leg 44 of the U-shaped inner boom portion, which trunnion 53 is coaxial with the front boom axis s-2.
The other link means 49, as here shown, comprises a pair of individual links that lie outwardly adjacent to the legs 44 of the U-shaped inner end portion of the boom. The rear end of each of the last-mentioned two links pivots about a trunnion 55 on the rear boom axis B-l, and each such trunnion 55 can comprise an extension of one of the trunnions comprising the rear boom joint element 37, which can project laterally outwardly beyond the bifurcations that carry it to provide for ~23~38~
the link connection. At its front end Pach of the last men-tioned individual links has a pivotal connection with a short trunnion 56 that is carried by a small lug 57 fixed on a forwardly projecting leg portion of the tower cap, said trunnion 56 of course being coaxial with the front fixed axis F~2.
It will be evident that the link means 47, 49 not only control the boom in its vertical movements, constraining it to swing about one or the other of the fixed axes F-l, F-2, but also impart lateral stability to the boom, confining it against side-to-side swinging and translatory movement relati~e to the tower.
~ o carry the hoisting cable 7 from behind the tower around to the outer end of the boom 6 and over the articulation means 8, there are, idler sheaves 59 mounted on top of a strut 58 that projects up from the tower cap 32 near the rear side of the tower.
From the foregoing description taken with the accompanying drawings it will be apparent that 8his invention provides simple, sturdy and inexpensive articulation means whereby the boom of a tower crane is so connected with the top of its tower that the boom swings about an axis which is centered between the front and back sides of the tower when the boom is in its range of working positions, and swings about an axis that is near the front side of the tower as it is brought to and from an inoperative position in which it extends down along the front side of the tower, transfer from one to the other of these axes being effected automatically as the boom passes through a transition position.
Brief Description of the Drawings In the accompanying drawings, which illustrate what is now regarded as a preferred embodiment of the invention:
Figure l is a view in side elevation of a tower crane em-bodying the principles of this invention with the boom in working position;
Figure 2 is a view similar to Figure l but showing the boom in its inoperative position;
Figure 3 is a top plan view of the articulation means of this invention;
~23~388~) Fig. 4 is a perspective viPw of the articulation means as seen from above and to the rear of the top of the tower;
Figs. 5, 6 and 7 are fragmentary views in side elevation showing successiye conditions of the articulation means as the boom swings down from the lower part of its range of working positions to its inoperative position.
Detailed Description of Preferred Embodiment of the In~ention A tower crane that embodies the principles of this in-Yention comprises a high upright tower 5 and a boom 6 that hasan outer end from which a load hoisting cable 7 depends and an inner end portion that is connected to the top of the tower 5 by means of articulation means 8 of this invention. The crane in this case has a base 10 equipped with crawler treads and comprises the usual platform 11 ~hich is mounted on the base for rotation relatiye to it about a vertical sluing axis.
The platform 11 in turn supports the tower 5 as well as such conyentional elements as an operator's cab, engine and winches.
When the crane is in operation, the boom 6 projects for-ward from the top of the tower 5, as shown in Fig. 1, and isswingable relati~e to the tower in a vertical plane, through a range of working positions in which the longitudinal center-line of the boom makes upward angles to the horizontal of between about 15 and 75. Such yertical swinging of the boom 6 enables a hoisted load to be moved towards and from the base 10 of the machine, while sluing motion provides for moving the hoisted load to the left and right. Vertical swinging of .
~238~380 the boom 6 in its range of working positions takes place about a first fixed axis F-l, which is defined by a first pair of engageable and disengageable joint elements as ex-plained hereinafter. That first fixed axis F-l is located midway between the front side 13 and the rear side 14 of the tower, so that the load forces imposed upon the top of the tower through that axis are centered relative to the tower and therefore impose no bending moments upon it.
As the boom is allowed to swing below its range of working positions, it passes through a transition position in which it extends substantially horizontally and in which a second pair of cooperating joint elements tdescribed herein-after) are automatically engaged to define a second fixed axis F-2, which is spaced a small distance forward of the front side 13 of the tower and ~hich is parallel to the first axis F-l. With continued downward swinging of the boom, the cooperating joint elements of the first pair are disengaged and the boom swings about the second axis F-2 until it reaches the inoperative or parking position shown in Fig. 2, wherein it extends downward along the front side of the boom. In swinging upward from the inoperative position, the boom first swings about the second or front axis F-2 until it reaches the above mentioned transition position, and then swings about the first axis F-l.
The articulation means 8 of this in~ention, which com-prises the cooperating joint elements that define these alternatively employed axes, is described in detail hereinafter.
~23~
At this point, however, certain other features should be noted in a crane that comprises the articulation means 8 of this invention.
The first axis F-l, which is centered on the tower 5 and about which the boom 6 swings in its range of working positions, extends across the inner end of the boom and is of course horizontal and transverse to the length of the boom.
However, the second or forward axis P-2 is spaced outwardly along the boom from its inner end, and therefore when the boom is in its inoperative position a short inner end portion 15 of it, substantially e~ual in length to the distance be-tween the fixed axes, projects above the top of the tower, as shown in Figs. 2 and 7.
For actuating the boom 6 to swing between its inoperative and its working positions, and through its range of working positions, a strut 17 is fixed on the inner end of the boom, extending substantially at right angles to the boom to project upward when the boom is in its working positions and to pro-ject forward when the boom is in its inoperative position. A
rigid diagonal brace 18 is connected between the strut 17 and the boom ~, and a pendant or tension cable 19 is connected between the tip of the strut 17 and the outer end of the boom. In like manner there is a strut 20 that projects rear-ward from the top of the tower 5, supported by a rigid brace 21 that extends diagonally down to the tower and having a pendant 22 connected between its tip and the bottom portion of the tower. A cable 2~ for actuating the boom 6 in its vertical swinging extends up from one of the winches, around ~238~31(~
an idler sheave 25 that is at the rear side of the tower and a distance below its top, thence around shea~es 26 at the tip of the horizontal strut 20, through sheaves 27 on the tip of the boom-carried strut 17, and back to a fixed connection 28 at the tip of the horizontal strut 20. It will be apparent that when this cable 24 is wound in, the tip of the strut 17 i5 drawn towards the tip of the horizontal strut 20, raising the outer end of the boom; whereas unwinding the cable 24 allows the outer end of the boom to descend. secause the strut 17 is mounted on the very inner end of the boom, which is above the leYel of the horizontal strut 20 when the boom is in its inoperative position (see Fig. 2) the two struts 17 and 20 can cooperate with the cable 24 for raising the boom from its inoperative position. Note that, for simplicity, the strut 17 is not shown in Figs. 3-7.
The base portion of the tower 5 is pivoted to the platform 11 so that the tower can be swung down forwardly from its erected position shown in the drawings to a horizontal position in which the boom 6 underlies it. Before the tower is swung down, the boom, in its inoperative position, is releasably latched to the tower, known latching means (not shown) being arranged to effect such latching automatically when the tower reaches its inoperative position. The latching means is of course manually released after the tower is erected and when the boom is to be swung up to its range of working positions.
The ~eans for swinging the tower between its erected and its horizontal positions is also known, comprising a gantry 30.
--ll--~38l3~
The articulation means 8 of this invention comprises a tower cap 32 that is fixed to the top o~ the tower and has a pair of legs 33 that project forward beyond the front side 13 of the tower. Fixed to the top of the tower cap are rear and front tower joint elements 35, 36 which respectively define the two fixed axes F-l and F-2 about which the boom swings and which cooperate with respective boom joint elements 37 and 38 that are fixed on the inner end portion of the boom. In this case the boom joint elements 37, 38 comprise trunnions and the tower joint elements 35, 36 comprise upwardly projecting lugs in which there are upwardly opening slots 41, 42 wherein the trunnions 37, 38 are respectively receivable; but it will be obvious that this relationship could be reversed in that the tower joint elements could comprise fixed trunnions and the boom joint elements could comprise lugs with downwardly opening slots.
As shown and preferred, each of the joint elements com-prises duplicate members spaced equal distances to opposite sides of a vertical plane of symmetry that contains the longitudinal centerlines of the tower and the boom. Thus the rear tower joint element 35 comprises a pair of upwardly projecting lugs on the tower cap 32, one near each lateral side of the tower, and the front tower joint element 36 like-wise comprises a pair of upwardly projecting lugs, one fixed on the front end of each of the leg portions 33 of the tower cap. The upwardly opening slot 41, 42 in every lug 35, 36 has a semicircular bottom end in which a trunnion is closely 1;~3~88~
rotatably receivable, the arcs of the bottom ends of these slots having their centers on the respective fixed axes F-l, F-2.
Each boom joint element 37, 38 comprises two coaxial trunnions that are spaced to opposite sides of the vertical plane of symmetry by a distance such as to be receivable in the slots of the lugs 35, 36 that comprise the cooperating tower joint element. Specifically, as best seen in Fig. 4, the inner end portion of the boom is U-shaped to have a pair of legs 44, and at the extreme inner end of the boom each leg 44 is in turn bifurcated and one of the coaxial trunnions that comprise the rear boom joint element 37 bridges across the bifurcations. As each of these trunnions 37 is recei~ed in a slot 41 of the rear tower joint element 35, the bifurca-tions of the boom leg overlie opposite faces of the lug thatcontains the slot 41, confining the boom against movement in directions along the boom axes. It will be seen that the trunnions that comprise the rear boom joint element 37 define a first boom axis B-l that coincides with the first fixed axis F-l when those trunnions are received in the slots 41, that is, when the boom joint element 37 is engaged with its cooperating tower joint element 35.
The coaxial trunnions that comprise the front boom joint element 38 are anchored in the legs 44 of the U-shaped inner end portion of the boom and project laterally outwardly from those legs. The legs 44 thus have their laterally outer faces close to the inner faces of the lugs that comprise the front tower joint element, 36 when the front joint elements 36, 38 ~23~ 30 are engaged, thereby cGnfining the boom against moYement parallel to the fixed axes F-l, F-2. It will be seen that the coaxial trunnions that comprise the front boom joint ele-ment 38 define a second or front boom axis B-2 that is parallel to the first boom axis B-l and is spaced from it by a distance e~ual to the distance between the fixed axes F-l and F-2, and the front boom axis B-2 coincides with the front fixed axis F-2 when the front joint elements 36, 38 are engaged.
It will be evident that when the boom is in its ranye of working positions the rear joint elements 35, 37 are engaged and the boom swings about the coinciding axes F-l and B-l; and when the boom is swinging to and from its inoperati~e position the front joint elements 36, 38 are engaged and the boom swings about the coinciding front axes F-2 and B-2. Because the boom axes B-l, B-2 are spaced apart by the same distance as the fixed axes F-l, F-2, the boom has a transition position, just below its range of working positions, in which both boom joint elements 37, 38 are fully engaged with their respectively cooperating tower joint elements 35, 36; and the boom passes through that transition position in the course of transferring its swinging motion from one to the other of the fixed axes F-l, F-2.
It will be evident that the boo~ must be constrained against moYement to a position in which neither pair of cooperating joint elements 35, 37 or 36, 38 is engaged. To that end, two link means 47 and 49 are connected between the tower cap and the boom, each link means in this case com-prising a pair of elongated and parallel links that are spaced . I .
~231~8~
equal distances to opposite sides of the plane of symmetry.
Each of the link means 47, 49 has at one end thereof a pivotal connection to the tower that is rotatable about the fixed axis F-l, F-2 defined by the tower joint element 35, 36 of one of the cooperating pairs of joint elements, and has at its other end a connection to the boom that is rotatable about the boom axis B-2, s-l defined by the boom joint element 38, 37 of the other cooperating pair of joint elements.
As here shown, one link means 47 comprises a pair of individual links that lie inwardly adjacent to the legs 44 of the U-shaped inner end portion of the boom. The rear end of each of those two links pivots about a short trunnion 51 carried by laterally spaced upwardly projecting lugs 52 that are fixed on the tower cap, the axes of said trunnions 51 coinciding with the rear fixed axis F-l defined by the rear tower joint element 37. The front end of each of those individual links pivots about a trunnion 53 that projects inwardly from a leg 44 of the U-shaped inner boom portion, which trunnion 53 is coaxial with the front boom axis s-2.
The other link means 49, as here shown, comprises a pair of individual links that lie outwardly adjacent to the legs 44 of the U-shaped inner end portion of the boom. The rear end of each of the last-mentioned two links pivots about a trunnion 55 on the rear boom axis B-l, and each such trunnion 55 can comprise an extension of one of the trunnions comprising the rear boom joint element 37, which can project laterally outwardly beyond the bifurcations that carry it to provide for ~23~38~
the link connection. At its front end Pach of the last men-tioned individual links has a pivotal connection with a short trunnion 56 that is carried by a small lug 57 fixed on a forwardly projecting leg portion of the tower cap, said trunnion 56 of course being coaxial with the front fixed axis F~2.
It will be evident that the link means 47, 49 not only control the boom in its vertical movements, constraining it to swing about one or the other of the fixed axes F-l, F-2, but also impart lateral stability to the boom, confining it against side-to-side swinging and translatory movement relati~e to the tower.
~ o carry the hoisting cable 7 from behind the tower around to the outer end of the boom 6 and over the articulation means 8, there are, idler sheaves 59 mounted on top of a strut 58 that projects up from the tower cap 32 near the rear side of the tower.
From the foregoing description taken with the accompanying drawings it will be apparent that 8his invention provides simple, sturdy and inexpensive articulation means whereby the boom of a tower crane is so connected with the top of its tower that the boom swings about an axis which is centered between the front and back sides of the tower when the boom is in its range of working positions, and swings about an axis that is near the front side of the tower as it is brought to and from an inoperative position in which it extends down along the front side of the tower, transfer from one to the other of these axes being effected automatically as the boom passes through a transition position.
Claims (4)
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:
1. A crane comprising an upright tower that has a top and front and rear sides, a boom that has an outer end from which a load hoisting cable can depend and an inner end, and articul-ation means providing a connection between said top of said tower and said inner end of said boom whereby said boom can swing through a range of upwardly projecting positions above horizontal about a horizontal rear fixed axis that is located at said top of said tower between said front and rear sides of said tower and whereby said boom can swing through a range of downwardly projec-ting positions below horizontal about a horizontal forward fixed axis that is located at said top of said tower and spaced forwar-dly from and parallel to said rear fixed axis, said downwardly projecting positions including an inoperative position wherein said boom extends substantially vertically downward along said front said of said tower, said articulation means comprising:
A. at least one rear pair of engageable and disengageable joint elements, (1) said rear pair comprising (a) a rear tower joint element fixed on the top of said tower on said rear fixed axis and (b) an associated rear boom joint element fixed on said inner end of said boom, B. at least one forward pair of engageable and disengageable joint elements, (1) said forward pair comprising (a) a forward tower joint element fixed on the top of said tower on said forward fixed axis and (b) an associated forward boom joint element fixed on said boom at a location outwardly of said rear boom joint element at a distance equal to that between said rear and forward axes, (2I) one joint element of said pair comprising a trunnion and (3) the other joint element of each forward pair comprising a slot (a) with a closed end that defines a seat on which the trunnion of an associated element can rotate when engaged there-with and (b) with an opposite open end to enable engagement and dis-engagment of the trunnion of an associated element in the course of substantially vertical relative motion of the boom joint ele-ments;
(4) said boom being swingable through said downwardly pro-jecting positions about said forward fixed axis whern said for-ward pair of joint elements are engaged and said rear pair of joint elements are disengaged.
(5) said boom being swingable through said upwardly project-ing positions about said rear fixed axis when said rear pair of joint elements are engaged and said forward pair of joint ele-ments are disengaged.
C. at least one elongated first link having (1) one end pivotally connected to the top of said tower on said rear fixed axis and (2) an opposite end pivotally connected to said boom on the same axis as said forward boom joint element;
D. at least one elongated second link having (1) one end fixedly connected to said boom on the same axis as said rear boom joint element and (2) an opposite end pivotally connected to the top of said tower and said forward fixed axis;
(3) said first and second links being operable to prevent said boom from moving relative to said tower to a position in which neither of said rear or forward pairs of joint elements is engaged; and E. means connected to said boom to effect swinging movement of said boom about either one of said rear fixed axis or said forward fixed axis.
A. at least one rear pair of engageable and disengageable joint elements, (1) said rear pair comprising (a) a rear tower joint element fixed on the top of said tower on said rear fixed axis and (b) an associated rear boom joint element fixed on said inner end of said boom, B. at least one forward pair of engageable and disengageable joint elements, (1) said forward pair comprising (a) a forward tower joint element fixed on the top of said tower on said forward fixed axis and (b) an associated forward boom joint element fixed on said boom at a location outwardly of said rear boom joint element at a distance equal to that between said rear and forward axes, (2I) one joint element of said pair comprising a trunnion and (3) the other joint element of each forward pair comprising a slot (a) with a closed end that defines a seat on which the trunnion of an associated element can rotate when engaged there-with and (b) with an opposite open end to enable engagement and dis-engagment of the trunnion of an associated element in the course of substantially vertical relative motion of the boom joint ele-ments;
(4) said boom being swingable through said downwardly pro-jecting positions about said forward fixed axis whern said for-ward pair of joint elements are engaged and said rear pair of joint elements are disengaged.
(5) said boom being swingable through said upwardly project-ing positions about said rear fixed axis when said rear pair of joint elements are engaged and said forward pair of joint ele-ments are disengaged.
C. at least one elongated first link having (1) one end pivotally connected to the top of said tower on said rear fixed axis and (2) an opposite end pivotally connected to said boom on the same axis as said forward boom joint element;
D. at least one elongated second link having (1) one end fixedly connected to said boom on the same axis as said rear boom joint element and (2) an opposite end pivotally connected to the top of said tower and said forward fixed axis;
(3) said first and second links being operable to prevent said boom from moving relative to said tower to a position in which neither of said rear or forward pairs of joint elements is engaged; and E. means connected to said boom to effect swinging movement of said boom about either one of said rear fixed axis or said forward fixed axis.
2. A crane according to claim 1 wherein each of said tower joint elements comprises a slot and wherein each of said boom joint elements comprises a trunnion.
3. A crane according to claim 1 including two of said rear pairs of joint elements laterally spaced apart from each other and including two of said forward pairs of joint elements laterally spaced apart from each other.
4. A crane according to claim 3 wherein each tower joint element comprises a slot and wherein each boom joint ele-ment comprises a trunnion.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US06/525,170 US4529094A (en) | 1983-08-22 | 1983-08-22 | Articulation for tower crane boom that has a parking position |
| US525,170 | 1983-08-22 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1238880A true CA1238880A (en) | 1988-07-05 |
Family
ID=24092219
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000461335A Expired CA1238880A (en) | 1983-08-22 | 1984-08-20 | Articulation for tower crane boom that has a parking position |
Country Status (7)
| Country | Link |
|---|---|
| US (1) | US4529094A (en) |
| JP (1) | JPS6061496A (en) |
| AU (1) | AU558784B2 (en) |
| CA (1) | CA1238880A (en) |
| DE (1) | DE3430747A1 (en) |
| FR (1) | FR2551041B1 (en) |
| GB (1) | GB2145391B (en) |
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| US4788820A (en) * | 1987-05-15 | 1988-12-06 | Kabushiki Kaisha Kobe Seiko Sho | Hydraulic circuit for large crane |
| US4930647A (en) * | 1989-01-24 | 1990-06-05 | Continental Plastics, Inc. | Tamper indicating closure system utilizing axially extending ratchet |
| FR2788758B1 (en) | 1999-01-27 | 2001-02-23 | Potain Sa | METHOD AND DEVICE FOR MOUNTING THE MASTER HEAD OF TOWER CRANES |
| US7814937B2 (en) * | 2005-10-26 | 2010-10-19 | University Of Southern California | Deployable contour crafting |
| DE202004017771U1 (en) * | 2004-11-16 | 2006-03-23 | Liebherr-Werk Ehingen Gmbh | crane boom |
| US7878348B2 (en) * | 2007-10-09 | 2011-02-01 | The United States Of America As Represented By The Administrator Of The National Aeronautics And Space Administration | Robotic-movement payload lifter and manipulator |
| US7980802B2 (en) * | 2007-10-24 | 2011-07-19 | T&T Engineering Services | Pipe handling apparatus with arm stiffening |
| US8469648B2 (en) | 2007-10-24 | 2013-06-25 | T&T Engineering Services | Apparatus and method for pre-loading of a main rotating structural member |
| US7946795B2 (en) * | 2007-10-24 | 2011-05-24 | T & T Engineering Services, Inc. | Telescoping jack for a gripper assembly |
| US8419335B1 (en) | 2007-10-24 | 2013-04-16 | T&T Engineering Services, Inc. | Pipe handling apparatus with stab frame stiffening |
| US7726929B1 (en) * | 2007-10-24 | 2010-06-01 | T&T Engineering Services | Pipe handling boom pretensioning apparatus |
| US8128332B2 (en) | 2007-10-24 | 2012-03-06 | T & T Engineering Services, Inc. | Header structure for a pipe handling apparatus |
| US7918636B1 (en) | 2007-10-24 | 2011-04-05 | T&T Engineering Services | Pipe handling apparatus and method |
| US9500049B1 (en) | 2008-12-11 | 2016-11-22 | Schlumberger Technology Corporation | Grip and vertical stab apparatus and method |
| US8408334B1 (en) | 2008-12-11 | 2013-04-02 | T&T Engineering Services, Inc. | Stabbing apparatus and method |
| US8371790B2 (en) | 2009-03-12 | 2013-02-12 | T&T Engineering Services, Inc. | Derrickless tubular servicing system and method |
| US8839966B2 (en) | 2009-03-31 | 2014-09-23 | Manitowoc Crane Companies, Llc | Folding jib main strut and transportable reeved strut caps |
| US8172497B2 (en) * | 2009-04-03 | 2012-05-08 | T & T Engineering Services | Raise-assist and smart energy system for a pipe handling apparatus |
| US8876452B2 (en) | 2009-04-03 | 2014-11-04 | T&T Engineering Services, Inc. | Raise-assist and smart energy system for a pipe handling apparatus |
| US9556689B2 (en) | 2009-05-20 | 2017-01-31 | Schlumberger Technology Corporation | Alignment apparatus and method for a boom of a pipe handling system |
| US8192128B2 (en) * | 2009-05-20 | 2012-06-05 | T&T Engineering Services, Inc. | Alignment apparatus and method for a boom of a pipe handling system |
| USD666784S1 (en) * | 2010-04-16 | 2012-09-04 | Liebherr-Werk Ehingen Gmbh | Crane |
| USD666375S1 (en) * | 2010-04-16 | 2012-08-28 | Liebherr-Werk Ehingen Gmbh | Crane |
| RU2564297C2 (en) | 2010-12-30 | 2015-09-27 | Т&Т Инжиниринг Сервисез Инк. | Quickly transported drilling rig |
| BRPI1100106B1 (en) * | 2011-01-20 | 2022-08-23 | Passini Montagem, Comércio E Locação De Equipamentos Ltda – Me | TOWER CRANE AND METHOD OF ASSEMBLY, DISASSEMBLY AND ASCENSION DISPLACEMENT IN ELEVATOR WELL |
| CN102275833B (en) * | 2011-05-26 | 2013-10-30 | 中联重科股份有限公司 | Crane, and suspension arm structure and arm lifting method thereof |
| RU2492132C2 (en) * | 2011-09-15 | 2013-09-10 | Борис Клеоникович Марысаев | Tower crane |
| US9091128B1 (en) | 2011-11-18 | 2015-07-28 | T&T Engineering Services, Inc. | Drill floor mountable automated pipe racking system |
| WO2013116632A1 (en) | 2012-02-02 | 2013-08-08 | United States Of America, As Represented By The Administrator Of The National Aeronautics And Space Administration | Tension stiffened and tendon actuated manipulator and a hinge for use therein |
| US9206021B2 (en) | 2012-09-26 | 2015-12-08 | Kobelco Cranes Co., Ltd. | Crane and crane assembling method |
| US9476267B2 (en) | 2013-03-15 | 2016-10-25 | T&T Engineering Services, Inc. | System and method for raising and lowering a drill floor mountable automated pipe racking system |
| JP6004537B2 (en) * | 2013-03-18 | 2016-10-12 | コベルコ建機株式会社 | jib |
| DE102013011489B4 (en) * | 2013-07-09 | 2021-09-16 | Liebherr-Werk Ehingen Gmbh | Tower crane |
| JP6348453B2 (en) * | 2015-05-27 | 2018-06-27 | 住友重機械建機クレーン株式会社 | crane |
| US10569415B2 (en) | 2016-08-31 | 2020-02-25 | United States Of America As Represented By The Administrator Of Nasa | Tension stiffened and tendon actuated manipulator |
| DE102016015385A1 (en) * | 2016-12-22 | 2018-06-28 | Liebherr-Werk Biberach Gmbh | Crane with folding jib |
| DE102018101705A1 (en) * | 2018-01-25 | 2019-07-25 | Liebherr-Werk Biberach Gmbh | tower crane |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE1100248B (en) * | 1956-08-03 | 1961-02-23 | Maschf Augsburg Nuernberg Ag | Construction crane |
| DE1254317B (en) * | 1964-04-15 | 1967-11-16 | Bielskie Zaklady Urzadzen Tech | Boom bearing on the tower of a self-assembling tower crane |
| US3934729A (en) * | 1969-04-09 | 1976-01-27 | General Crane Industries Limited | Tower crane |
| US3939988A (en) * | 1969-04-09 | 1976-02-24 | General Crane Industries Limited | Tower crane |
| JPS4859537A (en) * | 1971-11-29 | 1973-08-21 | ||
| DE2223665C2 (en) * | 1972-05-16 | 1973-11-29 | Eduard Prof. Dipl.-Ing. 6750 Kaiserslautern Herbert | crane |
| US3794184A (en) * | 1973-01-15 | 1974-02-26 | Joyce Burroughs Torregrossa | Crane |
-
1983
- 1983-08-22 US US06/525,170 patent/US4529094A/en not_active Expired - Lifetime
-
1984
- 1984-08-10 GB GB08420396A patent/GB2145391B/en not_active Expired
- 1984-08-16 AU AU31980/84A patent/AU558784B2/en not_active Ceased
- 1984-08-20 CA CA000461335A patent/CA1238880A/en not_active Expired
- 1984-08-21 JP JP59172535A patent/JPS6061496A/en active Granted
- 1984-08-21 FR FR8413014A patent/FR2551041B1/en not_active Expired - Lifetime
- 1984-08-21 DE DE19843430747 patent/DE3430747A1/en active Granted
Also Published As
| Publication number | Publication date |
|---|---|
| AU3198084A (en) | 1985-02-28 |
| FR2551041A1 (en) | 1985-03-01 |
| JPH0433717B2 (en) | 1992-06-03 |
| DE3430747C2 (en) | 1990-06-28 |
| FR2551041B1 (en) | 1990-06-15 |
| GB2145391A (en) | 1985-03-27 |
| GB8420396D0 (en) | 1984-09-12 |
| US4529094A (en) | 1985-07-16 |
| AU558784B2 (en) | 1987-02-05 |
| JPS6061496A (en) | 1985-04-09 |
| DE3430747A1 (en) | 1985-03-14 |
| GB2145391B (en) | 1986-03-05 |
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| Date | Code | Title | Description |
|---|---|---|---|
| MKEX | Expiry |